As we turned on to our neighborhood street we were greeted with bouncing star-like lights coming down our street....highly unusual. As we got closer, we realized it was lots of people jogging down the street with headlamps on. lol LOTS of people....maybe 40 or so by the time I stopped watching them. A group of them had stopped where a street comes into ours at a T intersection and they were drawing something on the ground with chalk....a big circle with direction I think.
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My first thought was that they were playing Cops and Robbers. My kids play this, but not in our neighborhood.....too close to the real thing here. But when I asked one of them what they were playing, he called out, "Just enjoying a run.....and beer!" hmmm I had to look it up. So I googled headlamps, run, chalk drawings.
They are 'Hashers'. I won't link to their sight because besides running and drinking (they end the run at a club or bar), they do a lot of off color talking on their website and do a lot of hooking up, if you know what I mean. And I think you do, so no need to mention specifics.
Apparently the full moon and for some reason Wednesdays in particular are the days to hash around town. It is a nation wide organization. (I need to just put a stop to this curiosity sometimes. Now I will be suspicious of people with headlamps.)
I think Geo-caching (also a sort of secret society of people with adventurous spirits) is a lot more tame and family friendly (and you can wear headlamps to do this too!). But I did learn something new....to me.